<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="./node_modules/vue/dist/vue.js"></script>
    <style>
        * {
            padding:0;
            margin:0;
            text-align: center;
        }

        header, footer{
            clear:both;
            background-color: gray;
        }

        #content>div{
            float:left;
        }
        .box{
            width:100%;
           
        }
        .left, .right{
            width:100px;
            background-color: burlywood;
        }
        .left{
            margin-left:-100%;
        }
        .right{
            margin-left:-100px;
        }
        .center{
            margin:0 100px;
            background-color: green;
        }

    </style>
</head>
<body>
    <header>header</header>
    <div id ="content">
        <!-- 双飞翼布局 -->
        <div class="box">
            <div class="center">中</div>
        </div> 
        <div class="left">左</div> 
        <div class="right">右</div>    
    </div>
    <footer>footer</footer>
</body>
</html>